Couplings

ABSTRACT

A coupling to connect the output shaft of a drive motor to an item of equipment has two coupling parts adapted to be connected to the motor and equipment, respectively. One of the coupling parts has adjustable jaws to facilitate connection to a variety of input shaft sizes while the other part is secured to an output shaft of the coupling. Driving motion is transmitted from one part to the other by means of driving dogs and an interposed cruciform member which permits minor misalignment of the shafts and absorbs shock loadings. The coupling parts are supported in assembled relationship by a housing secured to the drive motor and the coupling body.

Cheltenham, Victoria, Australia Filed: May-24, 1973 Appl. No.: 363,420

Foreign Application Priority Data Jan. 19. 1973 Australia 1967/73 References Cited UNITED STATES PATENTS 9/1914 Young 64/16 11/1926 Nielsen 279/64 12/1934 Stone 279/64 United States Patent r191 [111, 3,868,831 1 Stock Mar. 4, 11975 COUPLINGS 2,348,727 5/1944 Cote 403/183 Inventor: Ernest Rex Stock, McKinnon 2,848,239 8/1958 Ben amin et al 64/6 Vlctona Australia Primary E.\'aminer-Benjamin W. Wyche [73] Assignee: E. R. Stock Proprietary Limited, Assistant Examiner-Randall Heald [57] ABSTRACT A coupling to connect the output shaft of a drive motor to an item of equipment has two coupling parts adapted to be connected to the motor and equipment,

4 respectively. One of the coupling parts has adjustable jaws to facilitate connection to a variety of input shaft sizes while the other part is secured to an output shaft of the coupling. Driving motion is transmitted from one part to the other by means of driving dogs and an interposed cruciform member which permits minor misalignment of the shafts and absorbs shock loadings. The coupling parts are supported in assembled relationship by a housing secured to the drive motor and the coupling body.

12 Claims, 7 Drawing Figures PATENTEU HAR 4191s sum 1 or 3 PATENTEUMR 1% sum 2 pg 3 COUPLINGS BACKGROUND OF THE INVENTION This invention relates to an improved coupling and relates particularly to an improved coupling for driving a water pump, air compressor or similar equipment from the output shaft of an electric motor, stationary engine or the like.

Many items of equipment such as water pumps, air compressors and the like which are required to be driven by a prime mover, such as an electric motor, are fitted with a form of coupling to enable the driven shaft of the equipment to be coupled to the output shaft of the prime mover. In most cases, such form of coupling is restricted in use to the specific item of equipment and is generally unable to be used to couple that item of equipment to a range of prime movers. Further, electric motors and stationary engines are manufactured with a range of outward shaft diameters so that it is gen-.

erally necessary for a purchaser to select a coupling to suit the output shaft of the prime mover and the item of equipment. In some cases, special couplings must be manufactured for the purchaser of an item of equip ment such as a water pump or air compressor to enable that item to be used with the purchasers own prime mover. Naturally, the cost of manufacture of a specific coupling substantially increases the overall cost of the purchased equipment item.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved coupling which is suitable for use with a range of equipment items and a range of output drives from various prime movers.

It is another object of the present invention to provide an improved form of coupling which may be formed integral with an item of equipment and which permits that item of equipment to be coupled to a variety of electric motors or stationary engines or other prime movers. A still further object of the present invention is to provide an improved coupling for coupling the output shaft of a prime mover to the input shaft of an item of equipment such as a water pump or air compressor whereby the power unit and the item of equipment become a single unit.

A still further object of the present invention is to provide an improved form of universal coupling which obviates the need for exact alignment of the output shaft of the prime mover and the input shaft of the item of equipment coupled thereto.

Briefly stated, these objects are attained in a coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, and locating means mounting said body to the frame of driving or driven apparatus.

In a preferred form of the invention the output end of the coupling shaft is adapted to be secured to the impcller of a pump, or to a compressor unit or other item of equipment.

It is also preferred that the first and second drive parts are each formed with a pair of axially extending dogs, and the drive transmitting means comprises a member of cruciform shape formed of a fabric bakelite or similar material and adapted to engage between respective dogs of the first and second drive parts.

The shaft engaging means on the second coupling means may comprise three tapered jaws which engage with the drive shaft of a motor, and a collar threaded to the second coupling means for threaded movement axially relative thereto. The collar is formed with a jaw engaging section having a tapered internal surface corresponding to the jaw taper whereby screw threaded movement of the collar along the second coupling means causes variation of the diametral spacing of the jaws. A lock nut may also be threaded on the second drive part, the lock nut being adapted to engage with the collar to secure it relative to the second coupling means when the jaws are adjusted and fastened to the shaft of the drive motor.

OUTLINE OF THE DRAWINGS In order that the invention will be more readily understood and put into practical effect, one embodiment thereof will now be described with. reference to the accompanying drawings, wherein:

FIG. 1 is a sectional side elevational view of a coupling according to the invention,

FIG. 2 is a sectional end view taken along the lines 2-2 of FIG. 1,

FIG. 3 is a sectional end view taken along the lines 3-3 of FIG. 1,

FIG. 4 is a perspective view of one of the drive parts of the coupling showing the drive dogs,

FIG. 5 is a perspective view of the drive transmitting member,

FIG. 6 is a perspective view of the adjustable jaws, which engage the output shaft of a drive motor, located in slots in one of the drive parts,

FIG. 7 is a sectional side elevational view of a further form of coupling made according to this invention.

DESCRIPTION OF THE INVENTION Referring to FIGS. 1 to 6 of the drawings a coupling is shown for connecting the output shaft of an electric motor 12 to the impeller 13 of a water pump 14.

The coupling comprises a body 16 carrying a pair of ball bearings 17 axially spaced apart by spacers l8 and rotatably supporting a coupling shaft 19. The body 16 is attached by bolts 21 to the body of the water pump 14, and the pump impeller 13 is screwed directly to the end of the coupling shaft 19.

The driving end of the coupling shaft 19 is formed with a screw thread 22 to receive a correspondingly threaded first drive part 23. The first drive part 23 is locked on the driving end of the shaft 19 by means of a copper plug 24 and a screw 26 engaged in a threaded radial hole 27 in the drive part 23 The copper plug 24 is forced down onto the screw threads 22 by the said screw 26.

The first drive part 23 is formed with a pair of axially extending radially spaced dogs 28, more clearly shown in FIG. 4. A second substantially hollow cylindrical drive part 29, having a further pair of radially spaced, axially extending dogs 31, engages coaxially over the first drive part 23 with the dogs 31 positioned circumferentially spaced from those of the first drive part 23. A fabric bakelite drive transmitting member 32 of generally cross shape fits relatively snugly between the respective drive dogs 28, 31 of the first and second drive parts. Driving motion is thereby transmitted from one drive part 29 through its pair of drive dogs 31 to the drive transmitting member 32 and thenceto the dogs 28 of the other drive part 23. The drive transmit ting member 32 operates to absorb intermittent shock and minor misalignment of the drive motor shaft and the coupling output shaft 19. In this regard, it will be noted that no matter how precisely components are fitted together, misalignment of the parts can easily occur. The drive transmitting member 32 obviates any disadvantage through minor misalignment and acts to minimize wear of bearings and coupling components.

The forward end of the second drive part 29 is provided with three axially extending circumferentially and radially spaced guide segments 33. These segments 33 may be formed by milling radial slots 35 in the end portion of the drive part 29. The outer surfaces 34 of the guide segments 33 are formed with a taper of approximately l3. The cylindrical outer surface of the remainder of the second drive part 29 has a screw thread 36 along substantially the full length thereof.

A jaw adjusting collar 37 is threaded onto the screw thread 36 of the second drive part 29. The forward end of the jaw adjusting collar 37 has a substantially conically shaped jaw engaging section 38 with a tapered internal surface 39 to engage with correspondingly tapered external surfaces 40 on three jaws 41 located in the slots 35 in the forward end of the second drive part 29. The jaws 41 are located in position in the slots 35 and spread radially outwardly to engage with the jaw adjusting collar 37 by means of a resilient jaw spreader 42 within the end of the second drive part. It will be seen that screwed movement of the jaw adjusting collar 37 along the second drive part 29 results in expansion or contraction of the jaws 41 to enable them to be engaged with and locked to the output shaft of the drive motor 12. Preferably, one of the jaws 41 is formed with a key 43 for engagement with a keyway 44 in the output shaft 10 of the electric motor 12.

A lock nut 46 is also threadedly engaged with the second drive part 29 for locking the jaw adjusting collar 37 in position relative to the drive part 29. The lock nut 46 is formed with a shoulder 47 which engages with a complimentary shoulder 48 on the body 16 when the nut is screwed to the end of second drive part 29. Two grub screw holes 49, 50 are formed radially in the first and second drive parts 23, 29 to receive a grub screw (not shown) to secure the first and second drive parts together during assembly of the coupling to the output shaft of the electric motor 12. With the grub screw in position, the engagement of the complimentary shoulders 47, 48 locks the drive parts of the coupling to the body 16 and axially aligns the second drive part and associated jaws 41 with the coupling shaft 19.

Radial holes 52, 53 and 54 are provided in the jaw adjusting collar, the second drive part and the lock nut, respectively, for reception of appropriate tools or tommy bars for adjusting and locking purposes.

A split coupling housing 56 is bolted to the flange on the pump end of the coupling body 16. The housing 56 extends over the coupling parts and is provided with a flange 57 at the motor end thereof for bolting the coupling to the drive motor 12. The housing is axially split to enable one half thereof to be removed to facilitate attachment of the coupling to the drive shaft 10 of the motor 12. When the housing 56 is bolted to the motor 12 and the pump 14 is bolted to the coupling body 16, the motor 12 coupling and pump 14 become a rigid unit although the shaft connection within the coupling housing remains relatively flexible to absorb any intermittent shock or the like. The motor, pump and coupling may be transported as a portable unit and for this purpose a carrying handle (not shown) may be bolted to the coupling body 16 or housing 56.

In assembling the coupling to the output shaft 10 of the drive motor 12, one half of the coupling housing 56 is removed and the lock nut 46 is threaded along the second drive part to a position to expose the grub screw hole 49 for reception of the grub screw. The grub screw is inserted to lock the first and second drive parts 23, 29 together and the lock nut 46 is then screwed along the second drive part 29 to engage the coupling body 16. In this position, all parts of the coupling are securely locked together.

The jaw adjusting collar 37 is then screwed in or out to adjust the jaws 41 to receive the drive shaft 10 of the electric motor. The jaw having the key 43 therein is aligned with the keyway 44 of the electric motor shaft 10 and the coupling is then slid axially over the drive shaft 10. It will be appreciated that during this movement the jaw spreader 42 inside the coupling will be pushed inwardly by the movement of the end of the drive shaft 10 through the jaws 41.

The coupling is engaged over the shaft 10 the required distance to enable the lower part of the coupling housing 56 to engage with the motor flange face. The lower half of the housing 56 is then loosely bolted to the flange face to locate the coupling in position.

The jaw adjusting collar 37 is then adjusted to securely clamp the jaws 41 onto the shaft 10. The adjusting collar 37 may be rotated relative to the second drive part 29 by means of suitable bars engaged within the radial holes in the adjusting collar and the second drive part 29. The lower half of the housing 56 is then firmly bolted to the motor flange face to fix the coupling in final true alignment position. The lock nut 46 is screwed forwardly along the second drive part 29 to engage and lock the jaw adjusting collar 37 relative to the second drive part. The grub screw is removed thereby freeing the rigid connection between the first and second drive parts 23, 29 and the only connection therebetween is now through the drive transmitting member 32. This allows the coupling to become relatively flexible.

The top half of the coupling housing 56 is placed in position and bolted between the motor flange face and the coupling body.

It will be appreciated that the housing 56 may have meansfor securing the coupling to a base plate or the like rather than to the motor flange face. Obviously, other suitable means for locating and securing the coupling in position may also be used.

Referring to FIG. 7 of the drawings, a modified construction of coupling is shown. In this embodiment, at least one of the jaws 41 is formed with a radially inwardly projecting tail 40 which acts to limit the extent of axial engagement of the jaws 41 on the motor shaft 10.

In order to maintain the versatility of the coupling in accommodating a wide range of motor shaft sizes, the housing 56 is adjustable in length to provide for variations in shaft lengths. The length of the housing may be adjusted and fixed as desired by means of the bolts 55.

The modified coupling illustrated is basically similar to that previously described except that the drive transmitting member 32 is formed of phosphor-bronze metal. The second drive part 29 is also formed with a transverse wall 61 and the first drive part 23 is provided with a sealing ring 62 located in a circumferential groove 63 thus forming a sealed chamber for the drive transmitting member. A lubricant, such as grease, is packed in the chamber to lubricate the bearing surfaces of the drive dogs 28, 31 and the drive transmitting member 32.

I claim:

1. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, adjustable aligning means axially movable on the second coupling means and having shoulder means on a radial surface thereof engagable with complementary shoulder means on said body to releasably align the second coupling means relative to the body, and locating means mounting said body to the frame of driving or driven apparatus.

2. A coupling according to claim 1 wherein said drive transmitting means comprises a cruciform member engaged between pairs of axially extending dogs on both the first and second coupling means.

3. A coupling according to claim 1 wherein said second coupling means includes a hollow cylindrical portion located about, and substantially coaxial with, the first coupling means, said releasable locking means includes radial holes in said first and second coupling means arranged to be aligned to receive a locking screw securing the parts relative to each other.

4. A coupling according to claim 1 wherein said shaft engaging means includes a plurality of adjustable jaws in guide slots formed in the second coupling means the jaws having tapered outer surfaces, and a jaw adjusting collar screw threaded on the second coupling means, the jaw adjusting collar having an internal conical surface to coact with the tapered surfaces of the jaws to adjustably determine their radial spacing.

5. A coupling as claimed in claim 4 wherein resilient means are provided to bias the jaws radially apart and to maintain their tapered outer surfaces in contact with the conical inner surface of the jaw adjusting collar.

6. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, and locating means mounting said body to the frame of driving or driven apparatus, wherein said shaft engaging means includes a plurality of adjustable jaws in guide slots formed in the second coupling means the jaws having tapered outer surfaces, and a jaw adjusting collar screw threaded on the second coupling means, the jaw adjusting collar having an internal conical surface to coact with the tapered surfaces of the jaws to adjustably determine their radial spacing, andwherein said adjustable aligning means comprises a lock nut threaded on the outer surface of the second coupling means to engage and lock the jaw adjusting collar relative to the second coupling means, the lock nut having a shoulder formed on one radial face thereof which when the lock nut is threaded to the end of the second coupling means spaced from the jaw adjusting collar engages a complimentary shoulder on the coupling body to thereby axially align the second coupling means with the body.

7. A coupling according to claim 4 wherein at least one of the jaws has a radially inwardly directed projection which engages with the radial end of the driving or driven shaft of the apparatus to limit the extent of axial engagement of the coupling with that shaft.

8. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, and locating means mounting said body to the frame of driving or driven apparatus, wherein said locating means comprises an axially split housing totally enclosing the Coupling parts, the housing; having a flange face at one end thereof secured to a complimentary flange on the coupling body, and means on the housing for engagement with the frame or casing of the apparatus to which the coupling is connected.

9. A coupling according to claim 8 wherein the housing is formed of two telescoping sections adjustably secured together to allow adjustment of the axial length of the housing.

10. A drive coupling to connect the output shaft of a prime mover to the input shaft of apparatus to be driven by the prime mover comprising a coupling body, bearing means in the body supporting a coupling shaft for rotation relative to said body, a first coupling member secured to one end of the coupling shaft, the first member having a pair of radially spaced dogs extending axially in a direction away from said body, a second coupling member having at one end a substantially hollow cylindrical portion engaged coaxially over part of the first coupling member and having at its other end, remote from said body, shaft engaging means for coupling the second member to either the output shaft or the input shaft, a second pair of radially spaced dogs extending from said second member between the dogs of the first member, drive transmitting means positioned between said pairs of dogs, releasable lockingmeans for releasably locking said first and second members together, means on said second member movable to engage with said body to align said shaft engaging means with the coupling shaft when the first and second members are locked together, and coupling support means secured to the coupling body and to the frame or casing of either the prime mover or the driven apparatus.

11. A drive coupling according to claim 10 wherein the drive transmitting means comprises a member of cruciform shape, each arm of the member being located between one of each of the pairs of dogs to transmit motion therebetween.

12. A drive coupling according to claim 11 wherein the drive transmitting member is in a substantially sealed chamber between the first and second members,

the chamber being packed with a lubricant. 

1. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, adjustable aligning means axially movable on the second coupling means and having shoulder means on a radial surface thereof engagable with complementary shoulder means on said body to releasably align the secOnd coupling means relative to the body, and locating means mounting said body to the frame of driving or driven apparatus.
 2. A coupling according to claim 1 wherein said drive transmitting means comprises a cruciform member engaged between pairs of axially extending dogs on both the first and second coupling means.
 3. A coupling according to claim 1 wherein said second coupling means includes a hollow cylindrical portion located about, and substantially coaxial with, the first coupling means, said releasable locking means includes radial holes in said first and second coupling means arranged to be aligned to receive a locking screw securing the parts relative to each other.
 4. A coupling according to claim 1 wherein said shaft engaging means includes a plurality of adjustable jaws in guide slots formed in the second coupling means the jaws having tapered outer surfaces, and a jaw adjusting collar screw threaded on the second coupling means, the jaw adjusting collar having an internal conical surface to coact with the tapered surfaces of the jaws to adjustably determine their radial spacing.
 5. A coupling as claimed in claim 4 wherein resilient means are provided to bias the jaws radially apart and to maintain their tapered outer surfaces in contact with the conical inner surface of the jaw adjusting collar.
 6. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, and locating means mounting said body to the frame of driving or driven apparatus, wherein said shaft engaging means includes a plurality of adjustable jaws in guide slots formed in the second coupling means the jaws having tapered outer surfaces, and a jaw adjusting collar screw threaded on the second coupling means, the jaw adjusting collar having an internal conical surface to coact with the tapered surfaces of the jaws to adjustably determine their radial spacing, and wherein said adjustable aligning means comprises a lock nut threaded on the outer surface of the second coupling means to engage and lock the jaw adjusting collar relative to the second coupling means, the lock nut having a shoulder formed on one radial face thereof which when the lock nut is threaded to the end of the second coupling means spaced from the jaw adjusting collar engages a complimentary shoulder on the coupling body to thereby axially align the second coupling means with the body.
 7. A coupling according to claim 4 wherein at least one of the jaws has a radially inwardly directed projection which engages with the radial end of the driving or driven shaft of the apparatus to limit the extent of axial engagement of the coupling with that shaft.
 8. A drive coupling comprising a body, a shaft mounted for rotation in the body, first coupling means on one end of the shaft, second coupling means axially orientated with respect to the first coupling means, drive transmitting means between the first and second coupling means to transmit driving motion from one to the other, shaft engaging means on said second coupling means, releasable locking means to releasably lock said first and second coupling means together, and locating means mounting said body to the frame of driving or driven apparatus, wherein said locating means comprises an axially split housing totally enclosing the coupling parts, the housing having a flange face at one end thereof secured to a complimentary flange on the coupling body, and means on the housing for engagement with the frame or casing of the apparatus to which the coupling is connected.
 9. A coupling according to claim 8 wherein the housing is formed of two telescoping sections adjustably secureD together to allow adjustment of the axial length of the housing.
 10. A drive coupling to connect the output shaft of a prime mover to the input shaft of apparatus to be driven by the prime mover comprising a coupling body, bearing means in the body supporting a coupling shaft for rotation relative to said body, a first coupling member secured to one end of the coupling shaft, the first member having a pair of radially spaced dogs extending axially in a direction away from said body, a second coupling member having at one end a substantially hollow cylindrical portion engaged coaxially over part of the first coupling member and having at its other end, remote from said body, shaft engaging means for coupling the second member to either the output shaft or the input shaft, a second pair of radially spaced dogs extending from said second member between the dogs of the first member, drive transmitting means positioned between said pairs of dogs, releasable locking means for releasably locking said first and second members together, means on said second member movable to engage with said body to align said shaft engaging means with the coupling shaft when the first and second members are locked together, and coupling support means secured to the coupling body and to the frame or casing of either the prime mover or the driven apparatus.
 11. A drive coupling according to claim 10 wherein the drive transmitting means comprises a member of cruciform shape, each arm of the member being located between one of each of the pairs of dogs to transmit motion therebetween.
 12. A drive coupling according to claim 11 wherein the drive transmitting member is in a substantially sealed chamber between the first and second members, the chamber being packed with a lubricant. 